How Do "OpenMics" function?

My answer is pretty much the same as Keith's. And I, too, have had mixed experiences.

I know a few people who run / have run OMs and they have, in the main, brought their own gear and they have, in the main, been paid by the venue. A few of these venues do have their own PAs but they tend to be a bit... shall we say... road worn? Usually the OM organiser plays a few songs him/herself and then opens up the floor to those people who have put their name on the list. I prefer OMs that have a set time-limit - say ten minutes - rather than, say, three songs. I recall a Bob Dylan inspired OM with the three song rule and someone started with Desolation Row... But there seems to be an unwritten (and poor) rule that says if your three songs are under ten minutes then that's your lot anyway.

I've also been to OMs where the organisers (usually this occurs when it's a band) play about forty-five minutes themselves, then open up the floor for a while, before doing another forty-five minutes...

I don't mind OMs, but haven't really been to one in a year or more. They're great for new artists, old artists trying out new ideas, or in-between artists just wanting to play now that there are so few gigs (the OMs have replaced them all! And who can blame the venues? Why pay for a whole band when you can pay one bloke and get a bunch of other musicians to play for free and buy beer?).

We still have a few folk clubs around these parts but I don't know if they pay. I suspect not. I believe I'm blacklisted by the main folk organiser round these parts for not playing traditional folk so I keep away from that scene.

Derek

In my area, the 'open mics' tend to be in the City or large towns, generally, and are usually hosted by a local with a PA system who brings it and sets it up in the pub.
These tend to be a younger crowd, and more modern pop/rock music.
The Folk Night evenings or afternoons, tend to be acoustic unamplified, and more of a take-turns format, usually either traditional songs or (as I play), songs from the 60's and 70's but specifically Folk.
I actually prefer 'singaround sessions' which also tend to be unamplified, in pubs/cafe's/libraries and seem to be much more varied, from acapella singing, to poems, to every style of guitar music.
At most of the Folk or Singarounds, ppl do tend to join in, and make it more of a 'jam', which is nice, but the main focus is on take turns single performances.

As one of my many musical endeavours I often host open mics. I always get paid. In most venues PA has been supplied, occasionally I've had to take my own, but I always take a supply of spare cables & "fixes" like contact mics that will rescue me if pickups and the like fail. Either me or the venue provides a house guitar so if you happen to wander in and fancy doing a song there's something you can play. Generally you turn up and either add your name to a sheet, or speak to the host to book your slot. I prefer the speak-to-the-host approach as it allows me to give people more or less time according to how busy it is, and prevents the phenomena of people turning up to put their name down and then disappearing. If people turn up to sing I offer to provide accompaniment, as long as it is a song I am familiar with and everyone gets a brief mix during their first song and a warning when they are going to be next on. My favourite bit is usually the "all star jam" at the end when I drag up anyone who has played during the evening to do a song together.

"Folk clubs" take a variety of forms around here. Most are what I would call a sing-around where people take turns around the table/room to do a tune, although the crowd they draw is more silver-haired than an open mic they often seem to involve very little I would consider folk and a lot more I would think of as 60s & 70s pop. Others take the form of a featured guest + floor spots where a main act will play a full set & locals will do a few songs in the gaps. These days they usually seem to involve amplification, at least for the star act. Most of them do pay guest acts but often not much.

I've not encountered one of the old school folk clubs where you sign up, sit on a bar stool at the far end of the bowling alley and sing unaccompanied & unamplified for some time.